The Internet accelerates and magnifies virtually everything, including viciousness and compassion. One month, we celebrate a bullied girl’s Facebook-enhanced triumph over classmates who voted her homecoming queen as a joke; the next, we mourn the suicide of another teen whose tormenters relentlessly stalked her across the net and through multiple real-world moves.

The case of Amanda Todd, the 15-year-old Canadian girl who killed herself this week after a cascade of abuse following her victimization by a pedophile, illustrates what can happen when technology enables the most vile types of human behavior and how bullying can destroy psychological health.

The horror began when a predator took advantage of an overly trusting 12-year-old. A pedophile who stalked young girls with webcams called her “stunning, beautiful, perfect,” using the flattery to convince the child to reveal her breasts. Those few seconds of naivety set off a chain reaction that ultimately ended in Todd’s death. The man began to blackmail her — and when she refused to “put on a show” for him a year later, he e-mailed the pictures to her friends and family, eventually creating a Facebook page using her breasts as his profile picture.

While this should have resulted in outrage from Todd’s classmates over a pervert who should have been pursued and prosecuted, instead Todd was targeted by bullies as a “porn star.” Todd’s mother said that her daughter had learning difficulties, which may have played a role in the incident.

But the focus shouldn’t be on the victim, but on the perpetrators, who target the weak. Both bullies and pedophiles choose children who are helpless and desperate for any type of friendship or affirmation, kids who are isolated and feel bad about themselves for not fitting in but do not know how to tell when flattery or promises of friendship aren’t genuine but actual tools of cruel manipulation.

To start afresh, Todd switched schools after the first incident. But the experience had already triggered depression and an anxiety disorder. Research connects all of these problems with bullying: not only being a victim of bullying can spur depression and anxiety, but kids with mood disorders, like others who are different, are also especially likely to be targeted.

Todd’s mood disorders set off other problems, as well. In an attempt to feel better, she began drinking and taking drugs. Studies show that this misguided “solution” often appeals to students in Todd’s situation, both as an escape and because of the strong social identity associated with teen substance misuse. “Stoners” and “burnouts” in most situations tend to be more accepting and supporting of misfits.

Then the stalker reappeared, revealing the pictures again to her new classmates, prompting another round of bullying and isolation. Once more, she moved to try to escape.

But unfortunately, now settled reasonably well in another school, Todd again trusted the wrong people. Someone she described in her video as an “old guy friend,” got in touch, convincing her to “hook up” with him when his girlfriend was away. Word got out — and soon the girlfriend, her friends and even the guy himself showed up at Todd’s new school, to administer a beating that they videotaped. Her “reputation” caught up with her all over again.

In despair, the teen drank bleach, winding up in the hospital and then getting jeered online again for the unsuccessful suicide attempt. Desperate, she posted a video detailing her ordeal. “Every day, I think, why am I here?” reads one of the white cards that she holds throughout the silent black-and-white video. “I’m stuck. What’s left of me now? Nothing stops. I have nobody.” She attempted to take her life again, and this time, she succeeded. Even now, after her death, there are taunts posted among the tributes on her memorial page.

Did the Internet kill Amanda Todd? And why was the predator who created child pornography and who blackmailed her allowed to go free? Hacker activists Anonymous claim to have located the perpetrator, a 32-year-old Vancouver man who was charged with sexual assault with a minor in a case unrelated to Todd’s according to CTV.

But whatever becomes of the instigator of this terrible story, I think we need to remember the victim. Amanda Todd wasn’t able to protect herself: she wasn’t the villain, but she was treated like one. If we want to stop bullying, we can’t allow the ongoing targeting of those who can’t defend themselves to be seen as acceptable. We need to ask: What is wrong with a society in which other adolescents can see a 12-year-old who is blackmailed by a pedophile as a “porn star,” rather than a victim of child sexual abuse? How have we gotten here?

Ironically, as news of Todd’s death became known, a related story was playing out regarding the popular website, Reddit. Gossip site Gawker outed one of Reddit’s most prominent trolls, a man who anonymously posted creepy but not actually illegal photos of unwitting teenage girls. Reddit’s participants, however, weren’t outraged over the presence of quasi child porn that might be involved in tragic stories like that of Todd’s suicide, but, in a defend-the-perpetrator-blame-the-victim reaction eerily similar to that of Todd’s classmates, took issue with the fact that his real name had been made public. We’ve got to ask ourselves if this is the way we want our Web — and our children’s world — to be.

Szalavitz is a health writer at TIME.com. Find her on Twitter at @maiasz. You can also continue the discussion on TIME Healthland’s Facebook page and on Twitter at @TIMEHealthland.